diplococcus /dip′lōkok″əs/ pl. diplococci [Gk, diploos, double, kokkos, berry] , 1. n., a member of the Coccaceae family that occurs in pairs because of incomplete cell division. Diplococci are often found as parasites or saprophytes. 2. adj., describing bacteria of the Coccaceae family, which occur as pairs of cocci. Kinds include Streptococcus pneumoniae, Neisseria gonorrhoeae, Neisseria meningitidis.